Venetian blind



Dec. 28, 1937. H. H. MOHRFELD I 38 I VENETIAN BLIND Filed March 19, 1955 Patented Dec. 28, 1937 UNITED STATES PATENT OFFlCE Application March 19, 1935, Serial No. 11,855

(01. Isa-17 Claims.

This invention relates primarily to improvements in Venetian blinds, although it is applicable in principle to ventilators and windows of the louvre type.

A principal object of the invention is to provide slats of the blind;

Figs. 4 and 5 are diagrammatic views illustrating the manner in which the blind functions in its heat-insulating capacity, and 4 Fig. 6 is a fragmentary sectional view illustrating a modification within the scope of my invention.

With reference to the drawing, a blind made in accordance with my invention may comprise the usual assembly of elements providing a support for a plurality of slats I, said slats being arranged in parallel spaced relation, as shown in Fig. 2, and being simultaneously adjustable between substantially vertical and horizontal planes. With the slats in vertical position, the blind functions to substantially exclude light and air, while adjustment of the slats into the horizontal planes results in a maximum opening of the blind for admission of these elements. The general structure and mode of operation of blinds of this character are well known and form no part of the present invention.

The prior blinds of this class while highly effective in the light-shielding function have had only limited value in a heat-insulating capacity, this being due in large part to the fact that no provision was made for preventing deflection of heat rays from the slats to the rear of the blind. In accordance with my invention, I form the slats so that regardless of their position of angular adjustment substantially all the radiant heat energy impinging thereon will necessarily be reflected back to the outside of the blind, and will, therefore, be excluded from the space behind. The

blind thus becomes an effective heat-insulating barrier.

To this end I preferably form the slats, as shown in Fig. 3, with longitudinal corrugations of sharply defined angular form, and with the outer or upper faces, at least, presenting a highly reflective or polished surface. The apexes 2 and bottoms 3 of. the corrugations are as sharp as it may be practicable to make them so that the effective reflecting surface is restricted substantially to the areas constituting the inclined sides I of the corrugations. Preferably and as illustrated, these side surfaces are flat and form with the adjoining surfaces contained angles of ap- 5 proximately 90, and approximately 45 with the plane of the slat, although there may bevariations in these respects without departure from the invention. Slats .of this character may be readily and economically produced from sheet metal such as aluminum; or they may be constructed of materials not in themselves capable of affording the required reflecting surfaces and on which said surfaces may be produced. by a superficial layer of metallic foil or by a film of. 1 the desired character'deposited either by electrolytic action or by mechanical means. A slat so formed is illustrated in Fig. 6 wherein the superficial reflecting surface is indicated by the reference numeral 5.

The manner in which the slats function is graphically illustrated in Figs. '4 and 5, which show adjoining slats intwo different positions of adjustment. It will be noted that the radiant energy, indicated by broken lines, impinging upon the slats from substantially any angle will be reflected back either directly or indirectly in the general direction of their approach.

I claim:

1. A slat for Venetian blinds and the like, one face at least of said slat having a plurality of adjoining narrow highly reflecting surfaces disposed at an angle to the plane of the slat and to each'other, the juncture of said surfaces being of. clearly defined angular formation.

2. A slat for Venetian blinds and the like consisting of a longitudinally corrugated strip, said corrugations being narrow and of sharply defined angular formation with the sides thereof extending at angles to the plane of said strip of approximately 45 and having highly reflecting surfaces.

3. A slat for Venetian blinds and the like comprising a metallic strip formed with narrow longitudinal corrugations of sharply defined angular formation, said corrugations presenting polished highly reflecting surfaces extending at an angle to the plane of the slat of. approximately 45.

4. A heat insulating slat for Venetian blinds and the like, said slat-having'contiguous longitudinal narrow and sharply angular corrugations, the sides of said corrugations constituting reflecting surfaces and extending at an angle to the plane of the slat, said slat being adapted for conventional assembly with like slats to form the said blind, and said corrugations being propor- 55 tioned and arranged to deflect a majorportion of the radiant energy emanating from a source at one side 01' said blind and striking the latter back upon itself to thereby effectively exclude the said radiant energy from the area at the opposite side of the blind.

5. A heat insulating slat tor Venetian blinds and the like, said slat having a plurality of longitudinal sharply angular corrugations of approximately 90 included angle, the sides of said corrugations extending approximately at an angle of arcane HERBERT H. MOHRFELD. 

